In general, a mobile communication system establishes and operates a system that can provide performance required at a peak time when usage becomes maximum. However, since the mobile communication system wastes energy while using 50% or less of the performance at an off-peak time, energy saving is required for reducing system maintenance cost.
To this end, an energy saving technology of a general mobile communication system saves the energy through a method for minimizing energy used in devices (e.g., a CPU, a fan, and the like) constituting the system and a method for extending coverage of a base station selected at the off-peak time and switching off peripheral base stations through controlling the mobile communication system.
However, the technologies have a problem in that the technologies cannot actively cope with the energy saving and a sudden traffic increase in a heterogeneous network environment in which a lot of small cells are high densely overlapped and installed in a macro cell in order to process heavy mobile traffic.